Caption: Thomas Alva Edison (1847-1931), American inventor. At the age of 23, Edison invented a stock ticker that he sold to a Wall Street firm for 30,000 dollars. With this money, he founded a firm of engineers that turned out inventions like wax paper and the mimeograph. In 1876 he set up a research laboratory in Menlo Park, New Jersey. Here he invented the phonograph, improved the telephone and, after thousands of experiments, succeeded in making a practical light bulb. During his lifetime Edison filed a total of 1069 patents, a record no other inventor has ever approached.